Drivers and screw drivers have been known in the art for some time now. They are available for both low-torque and high-torque applications. Low torque variety may be used for machine screws and high torque variety may be used for wood screws, machine bolts or lag bolts. One such driver known in the art is a push-type spiral ratchet screwdriver or otherwise known as Yankee screwdriver. The function of the Yankee screwdriver is to provide torque to a screwdriver bit with axial movement of its handle. The up and down motion of the handle is converted to the rotary motion of the screwdriver bit using a driver mechanism that is used to fasten/unfasten a screw.
But the Yankee screwdriver also has disadvantages. The Yankee screwdriver has a spindle that is required to be held by a hand of the user while the other hand pushes/pulls the handle grip. This causes the respective wrists of the user to be in an uncomfortable position and causes inconvenience to the user. This inconvenience significantly increases when the user has to perform the fastening operation repeatedly for a predetermined duration. Prolonged usage causes pain in the user's fingers of the hand holding the spindle. Moreover, only a limited torque may be generated using a Yankee screwdriver. High torque applications require more force to be applied by the user which is not feasible for a user who performs such operations for long durations.
Therefore, there remains a need in the art for a spiral ratchet driver with a crank and slider mechanism which does not suffer from above mentioned deficiencies and provides a cost-effective solution to the above mentioned problems.
Any discussion of the background art throughout the specification should in no way be considered as an admission that such background art is prior art nor that such background art is widely known or forms part of the common general knowledge in the field.